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炸药爆轰驱动超高速击波管的数值摸拟  [PDF]
刘尔岩,袁仙春,廖振民
高压物理学报 , 1996, DOI: 10.11858/gywlxb.1996.03.011
Abstract: 高能炸药(HE)柱壳沿轴向传播的稳定态爆轰,在置于炸药柱壳内部的泡沫塑料(工作流体)中产生很强的轴向击波,达到极高的压力和能量密度。适当设计,可使工作流体的流动接近一稳定态,与炸药爆轰以相同的相速度前进。击波阵面后的工作流体可用Nozzle流动方程很好地描述[1],Nozzle收缩段中的流动不受散开段流动的影响。利用这一性质,可以设计出达到极高压力和能量密度的超高速击波管,并且不受管壁物质强度的限制。数值模拟计算给出了上述稳定态物理图象,并显示出开始阶段轴向击波的形成过程及其后对稳定态的逼近,计算结果及物理图象与理论分析符合得很好。
爆轰驱动飞片击靶波形精密控制技术  [PDF]
金柯,习锋,谭叶,刘晓海,戴诚达,蔡灵仓,吴强
高压物理学报 , 2013, DOI: 10.11858/gywlxb.2013.06.003
Abstract: 以有效装药长度模型为基础,通过沿径向向中心方向逐渐增加低阻抗材料缓冲层厚度的方法,实现了飞片击靶波形的精密控制。实验结果显示,在Φ80mm范围内飞片击靶波形差小于80ns,一维平面冲击波有效使用范围由原来的Φ40mm提升至Φ80mm,可以布置实验样品的面积提高了约3倍。以此爆轰加载装置为平台,测量了钽的冲击Hugoniot物态方程参数和无氧铜的高压声速数据,实验结果与以往的实验数据吻合得很好,表明该技术可用于材料多物理量联合测量的精密物理实验研究。
新Agegraphic快子暗能量模型再探讨
Revisit of New Agegraphic Tachyon Dark Energy Model
 [PDF]

崔晶磊, 张敬飞
Astronomy and Astrophysics (AAS) , 2013, DOI: 10.12677/AAS.2013.12002
Abstract:
agegraphic暗能量模型是依据量子力学的不确定性关系和广义相对论中的引力效应提出的。作为暗能量的候选者之一,动力学标量场被认为是暗能量基本理论的有效描述。本文把新agegraphic暗能量和标量场对应起来,构造具有新agegraphic暗能量性质的标量场模型,并利用观测数据来确定该标量场的拉氏量具体形式。本文考虑由暗能量、物质和辐射组成的平坦宇宙,通过标量场之一的快子场和新agegraphic暗能量的对应构造一个新agegraphic快子暗能量模型。参考最新拟合的模型参数n、哈勃常数h\"\",得到新agegraphic快子暗能量模型标量场势能\"\"和快子场\"\"的演化。
New agegraphic dark energy model is proposed based on the gravitational effect in general relativity together with the uncertainty relation of quantum mechanics. As one among candidates for dark energy, dynamical scalar field model can be viewed as an effective description of the underlying theory of dark energy. We reconstruct a scalar field to describe the cosmological evolution of the new agegraphic dark energy through the correspondence relationship be-tween new agegraphic dark energy and scalar field like tachyon field. In this paper, we reconstruct new agegraphic tachyon dark energy model, in a flat universe with dark energy, matter and radiation. Subsequently, we obtain the dy-namical evolution of the tachyon potential ??V? and the tachyon scalar field ??z? by the best-fit parameters: model parameter n, the Hubble parameter h and constrained by the latest observational data.
击顶制导  [PDF]
兵工学报 , 1992,
Abstract: ?论述了反坦克导弹精确制导发展的一个重要问题:击顶制导。给出了准三点导引法和适用于遥控反坦克导弹的掠飞击顶制导律;准比例导引法和适用于自寻的反坦克导弹的俯冲击顶制导律;以及实现上述两种击顶制导律的三通道参数最优击顶数字控制器。
The cosmology of the Fab-Four  [PDF]
Edmund J. Copeland,Antonio Padilla,Paul M. Saffin
Physics , 2012, DOI: 10.1088/1475-7516/2012/12/026
Abstract: We have recently proposed a novel self tuning mechanism to alleviate the famous cosmological constant problem, based on the general scalar tensor theory proposed by Horndeski. The self-tuning model ends up consisting of four geometric terms in the action, with each term containing a free potential function of the scalar field; the four together being labeled as the Fab-Four. In this paper we begin the important task of deriving the cosmology associated with the Fab-Four Lagrangian. Performing a phase plane analysis of the system we are able to obtain a number of fixed points for the system, with some remarkable new solutions emerging from the trade-off between the various potentials. As well as obtaining inflationary solutions we also find conventional radiation/matter-like solutions, but in regimes where the energy density is dominated by a cosmological constant, and where we do not have any explicit forms of radiation or matter. Stability conditions for matter solutions are obtained and we show how it is possible for there to exist an extended period of `matter domination' opening up the possibility that we can generate cosmological structures, and recover a consistent cosmology even in the presence of a large cosmological constant.
网络爆轰驱动飞片的设计技术  [PDF]
张友君,谷岩,裴晓阳,杜金梅,杨佳,喻寅
爆炸与冲击 , 2012, DOI: 10.11883/1001-1455(2012)05-0542-05
Abstract: ?提出使用炸药网络爆轰技术,设计了一种新型的低速飞片击靶加载装置,结合数值模拟和实验测量,对驱动飞片的速度、平面性及装置结构参数进行了系统分析。实验结果表明,无氧铜飞片可以使直径100mm、厚度3mm的飞片在飞行距离2mm内达到稳定的飞行状态,击靶速度在200~350m/s范围内连续可调,飞片击靶平面范围大、速度均匀、平面性好,为实现低冲击应力的一维应变加载提供了参考。
Spherical Cows in the Sky with Fab Four  [PDF]
Nemanja Kaloper,McCullen Sandora
Physics , 2013, DOI: 10.1088/1475-7516/2014/05/028
Abstract: We explore spherically symmetric static solutions in a subclass of unitary scalar-tensor theories of gravity, called the `Fab Four' models. The weak field large distance solutions may be phenomenologically viable, but only if the Gauss-Bonnet term is negligible. Only in this limit will the Vainshtein mechanism work consistently. Further, classical constraints and unitarity bounds constrain the models quite tightly. Nevertheless, in the limits where the range of individual terms at large scales is respectively Kinetic Braiding, Horndeski, and Gauss-Bonnet, the horizon scale effects may occur while the theory satisfies Solar system constraints and, marginally, unitarity bounds. On the other hand, to bring the cutoff down to below a millimeter constrains all the couplings scales such that `Fab Fours' can't be heard outside of the Solar system.
直接水击公式研究  [PDF]
马跃先,周琼,李世英,吴昊
人民黄河 , 2007,
Abstract: ?对joukowsky水击公式推导过程进行了分析,认为其推导过程中忽略了不该忽略的二阶微量.以动量定理为基础建立微分方程,考虑水体可压缩性和管壁弹性,得到不同于joukowsky水击公式的直接水击公式,与相关研究文献进行比较后认为,所建公式比joukowsky公式更合理.
Single chain Fab (scFab) fragment
Michael Hust, Thomas Jostock, Christian Menzel, Bernd Voedisch, Anja Mohr, Mariam Brenneis, Martina I Kirsch, Doris Meier, Stefan Dübel
BMC Biotechnology , 2007, DOI: 10.1186/1472-6750-7-14
Abstract: Here, we demonstrate that the introduction of a polypeptide linker between the fragment difficult (Fd) and the light chain (LC), resulting in the formation of a single chain Fab fragment (scFab), can lead to improved production of functional molecules. We tested the impact of various linker designs and modifications of the constant regions on both phage display efficiency and the yield of soluble antibody fragments. A scFab variant without cysteins (scFabΔC) connecting the constant part 1 of the heavy chain (CH1) and the constant part of the light chain (CL) were best suited for phage display and production of soluble antibody fragments. Beside the expression system E. coli, the new antibody format was also expressed in Pichia pastoris. Monovalent and divalent fragments (DiFabodies) as well as multimers were characterised.A new antibody design offers the generation of bivalent Fab derivates for antibody phage display and production of soluble antibody fragments. This antibody format is of particular value for high throughput proteome binder generation projects, due to the avidity effect and the possible use of common standard sera for detection.The production of functional antibody fragments in E. coli was first described by Skerra and Plückthun [1]. Key to this success was production in the periplasm, where the oxidizing environment allows the formation of disulphide bonds. Later, the linkage of the variable regions by a 15–25 amino acid linker of both Fv chains improved the expression of antibody fragments in E. coli [2,3]. However, these so called single chain fragment variable (scFv) have the tendency to form aggregates and are relatively unstable over longer periods of time [4]. Furthermore, some scFvs show a reduced affinity of up to one order of magnitude compared to the corresponding Fab fragments [5]. Only in rare cases have scFvs with a higher affinity than the associated Fab been found [6]. Because they are double the molecular size, and require the produ
人-鼠嵌合Fab片段的温度诱导表达
昝虹,叶敏
生物工程学报 , 1997,
Abstract: 构建了具有λPRPL启动子高效表达人鼠嵌合Fab片段的温度诱导表达型载体pHZ01。并在大肠杆菌中表达了三种嵌合Fab片段:抗前列腺特异抗原(PSA)的嵌合Fab.抗溶菌酶(HEL)的嵌合Fab和抗破伤风类毒素(TT)的嵌合Fab.三种表达的可溶 性嵌合Fab都具有特异结合抗原的能力,嵌合Fab的CHI和CK区均为人源的。较之鼠源 Fab具有更好的应用前景。
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